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The giraffe is a large African hoofed mammal belonging to the genus ''Giraffa''. It is the tallest living terrestrial animal and the largest ruminant on Earth. Traditionally, giraffes were thought to be one species, '' Giraffa camelopardalis'', with nine
subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
. Most recently, researchers proposed dividing them into up to eight
extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extinct, ...
species due to new research into their
mitochondrial A mitochondrion (; ) is an organelle found in the cells of most Eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is use ...
and nuclear DNA, as well as morphological measurements. Seven other extinct species of ''Giraffa'' are known from the fossil record. The giraffe's chief distinguishing characteristics are its extremely long neck and legs, its horn-like ossicones, and its spotted
coat A coat typically is an outer garment for the upper body as worn by either gender for warmth or fashion. Coats typically have long sleeves and are open down the front and closing by means of buttons, zippers, hook-and-loop fasteners, toggles, a ...
patterns. It is classified under the family Giraffidae, along with its closest extant relative, the okapi. Its scattered range extends from
Chad Chad (; ar, تشاد , ; french: Tchad, ), officially the Republic of Chad, '; ) is a landlocked country at the crossroads of North and Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic ...
in the north to South Africa in the south, and from Niger in the west to Somalia in the east. Giraffes usually inhabit
savannah A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the Canopy (forest), canopy does not close. The open canopy allows sufficient light to rea ...
s and woodlands. Their food source is leaves, fruits, and flowers of woody plants, primarily
acacia ''Acacia'', commonly known as the wattles or acacias, is a large genus of shrubs and trees in the subfamily Mimosoideae of the pea family Fabaceae. Initially, it comprised a group of plant species native to Africa and Australasia. The genus na ...
species, which they browse at heights most other herbivores cannot reach.
Lion The lion (''Panthera leo'') is a large Felidae, cat of the genus ''Panthera'' native to Africa and India. It has a muscular, broad-chested body; short, rounded head; round ears; and a hairy tuft at the end of its tail. It is sexually dimorphi ...
s,
leopard The leopard (''Panthera pardus'') is one of the five extant species in the genus '' Panthera'', a member of the cat family, Felidae. It occurs in a wide range in sub-Saharan Africa, in some parts of Western and Central Asia, Southern Russia, a ...
s,
spotted hyena The spotted hyena (''Crocuta crocuta''), also known as the laughing hyena, is a hyena species, currently classed as the sole extant member of the genus ''Crocuta'', native to sub-Saharan Africa. It is listed as being of least concern by the IUC ...
s, and African wild dogs may prey upon giraffes. Giraffes live in herds of related females and their offspring or bachelor herds of unrelated adult males, but are gregarious and may gather in large aggregations. Males establish social hierarchies through "necking", combat bouts where the neck is used as a weapon. Dominant males gain mating access to females, which bear sole responsibility for raising the young. The giraffe has intrigued various ancient and modern cultures for its peculiar appearance, and has often been featured in paintings, books, and cartoons. It is classified by the International Union for Conservation of Nature (IUCN) as
vulnerable Vulnerable may refer to: General * Vulnerability * Vulnerability (computing) * Vulnerable adult * Vulnerable species Music Albums * ''Vulnerable'' (Marvin Gaye album), 1997 * ''Vulnerable'' (Tricky album), 2003 * ''Vulnerable'' (The Used album) ...
to extinction and has been extirpated from many parts of its former range. Giraffes are still found in numerous
national park A national park is a nature park, natural park in use for conservation (ethic), conservation purposes, created and protected by national governments. Often it is a reserve of natural, semi-natural, or developed land that a sovereign state dec ...
s and game reserves, but estimates as of 2016 indicate there are approximately 97,500 members of ''Giraffa'' in the wild. More than 1,600 were kept in zoos in 2010.


Etymology

The name "giraffe" has its earliest known origins in the Arabic word (), perhaps borrowed from the animal's Somali name . The Arab name is translated as "fast-walker". In early Modern English the spellings and were used, probably directly from the Arabic, and in Middle English and , . The Italian form arose in the 1590s. The modern English form developed around 1600 from the
French French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with Franc ...
. "Camelopard" is an
archaic Archaic is a period of time preceding a designated classical period, or something from an older period of time that is also not found or used currently: *List of archaeological periods **Archaic Sumerian language, spoken between 31st - 26th cent ...
English name for the giraffe; it derives from the Ancient Greek καμηλοπάρδαλις (''kamēlopárdalis''), from κάμηλος (''kámēlos''), "
camel A camel (from: la, camelus and grc-gre, κάμηλος (''kamēlos'') from Hebrew or Phoenician: גָמָל ''gāmāl''.) is an even-toed ungulate in the genus ''Camelus'' that bears distinctive fatty deposits known as "humps" on its back. C ...
", and πάρδαλις (''párdalis''), "
leopard The leopard (''Panthera pardus'') is one of the five extant species in the genus '' Panthera'', a member of the cat family, Felidae. It occurs in a wide range in sub-Saharan Africa, in some parts of Western and Central Asia, Southern Russia, a ...
", referring to its camel-like shape and leopard-like colouration.


Taxonomy


Evolution

The giraffe is one of only two living genera of the family Giraffidae in the order Artiodactyla, the other being the okapi. The family was once much more extensive, with over 10 fossil
genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...
described. The elongation of the neck appears to have started early in the giraffe lineage. Comparisons between giraffes and their ancient relatives suggest vertebrae close to the skull lengthened earlier, followed by lengthening of vertebrae further down. One early giraffid ancestor was ''
Canthumeryx ''Canthumeryx'' is an extinct genus of primitive giraffid artiodactyls. It is the close ancestor of giraffe The giraffe is a large African hoofed mammal belonging to the genus ''Giraffa''. It is the tallest living terrestrial animal and ...
'' which has been dated variously to have lived 25–20 million years ago (mya), 17–15 mya or 18–14.3 mya and whose deposits have been found in Libya. This animal resembled an antelope and had a medium-sized, lightly-built body. '' Giraffokeryx'' appeared 15–12 mya on the Indian subcontinent and resembled an okapi or a small giraffe, and had a longer neck and similar ossicones. ''Giraffokeryx'' may have shared a clade with more massively built giraffids like '' Sivatherium'' and '' Bramatherium''. Giraffids like '' Palaeotragus'', '' Shansitherium'' and '' Samotherium'' appeared 14 mya and lived throughout Africa and Eurasia. These animals had broader skull with reduced frontal cavities. ''Paleotragus'' resembled the okapi and may have been its ancestor. Others find that the okapi lineage diverged earlier, before ''Giraffokeryx''. ''Samotherium'' was a particularly important transitional fossil in the giraffe lineage, as the length and structure of its cervical vertebrae were between those of a modern giraffe and an okapi, and its neck posture was likely similar to the former. '' Bohlinia'', which first appeared in southeastern Europe and lived 9–7 mya, was likely a direct ancestor of the giraffe. ''Bohlinia'' closely resembled modern giraffes, having a long neck and legs and similar ossicones and dentition. ''Bohlinia'' colonised China and northern India and produced the ''Giraffa'' which, around 7 mya, reached Africa. Climate changes led to the extinction of the Asian giraffes, while the African giraffes survived and radiated into new species. Living giraffes appear to have arisen around 1 mya in eastern Africa during the Pleistocene. Some biologists suggest the modern giraffes descended from '' G. jumae''; others find '' G. gracilis'' a more likely candidate. ''G. jumae'' was larger and more robust, while ''G. gracilis'' was smaller and more slender. The changes from extensive forests to more open habitats, which began 8 mya, are believed to be the main driver for the evolution of giraffes. During this time, tropical plants disappeared and were replaced by arid C4 plants, and a dry
savannah A savanna or savannah is a mixed woodland-grassland (i.e. grassy woodland) ecosystem characterised by the trees being sufficiently widely spaced so that the Canopy (forest), canopy does not close. The open canopy allows sufficient light to rea ...
emerged across eastern and northern Africa and western India. Some researchers have hypothesised that this new habitat coupled with a different diet, including acacia species, may have exposed giraffe ancestors to toxins that caused higher mutation rates and a higher rate of evolution. The coat patterns of modern giraffes may also have coincided with these habitat changes. Asian giraffes are hypothesised to have had more okapi-like colourations. The giraffe genome is around 2.9 billion
base pair A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...
s in length compared to the 3.3 billion base pairs of the okapi. Of the proteins in giraffe and okapi genes, 19.4% are identical. The divergence of giraffe and okapi lineages dates to around 11.5 mya. A small group of regulatory genes in the giraffe appear to be responsible for the animal's height and associated circulatory adaptations.


Species and subspecies

The International Union for Conservation of Nature (IUCN) currently recognises only one species of giraffe with nine subspecies. Carl Linnaeus originally classified living giraffes as one species in 1758. He gave it the binomial name '' Cervus camelopardalis''. Mathurin Jacques Brisson coined the genus ''Giraffa'' in 1762. During the 1900s, various taxonomies with two or three species were proposed. A 2007 study on the genetics of giraffes using mitochondrial DNA suggested at least six lineages could be recognised as species. A 2011 study using detailed analyses of the morphology of giraffes, and application of the phylogenetic species concept, described eight species of living giraffes. A 2016 study also concluded that living giraffes consist of multiple species. The researchers suggested the existence of four species, which have not exchanged genetic information between each other for 1 to 2 million years. A 2020 study showed that depending on the method chosen, different taxonomic hypotheses recognizing from two to six species can be considered for the genus ''Giraffa''. That study also found that multi-species coalescent methods can lead to taxonomic over-splitting, as those methods delimit geographic structures rather than species. The three-species hypothesis, which recognises ''G''. ''camelopardalis'', ''G''. ''giraffa'', and ''G''. ''tippelskirchi'', is highly supported by phylogenetic analyses and also corroborated by most population genetic and multi-species coalescent analyses. A 2021 whole genome sequencing study suggests the existence of four distinct species and seven subspecies. The cladogram below shows the phylogenetic relationship between the four proposed species and seven subspecies based on the genome analysis. Note the eight lineages correspond to eight of the traditional subspecies in the one species hypothesis. The Rothschild giraffe is subsumed into ''G. camelopardalis camelopardalis''. The following table compares the different hypotheses for giraffe species. The description column shows the traditional nine subspecies in the one species hypothesis. The first extinct species to be described was ''Giraffa sivalensis'' Falconer and Cautley 1843, a reevaluation of a vertebra that was initially described as a fossil of the living giraffe. While taxonomic opinion may be lacking on some names, the extinct species that have been published include: *''Giraffa gracilis'' *''
Giraffa jumae ''Giraffa jumae'' is an extinct species of artiodactyla, even-toed ungulate in the Giraffidae family (biology), family. The species ranged from Malawi to Chad with a possible occurrence of the species or a closely related species found in Turkey. ...
'' *'' Giraffa priscilla'' *''Giraffa pomeli'' *''Giraffa punjabiensis'' *'' Giraffa pygmaea'' *''
Giraffa sivalensis ''Giraffa sivalensis'' is an extinct species of giraffe occurring in Asia during the Pliocene and Pleistocene epochs. Almost perfectly preserved cervical vertebrae have been found, as well as humeri, radii, metacarpals and teeth A tooth ( : ...
'' *''
Giraffa stillei ''Giraffa stillei'' is an extinct species of giraffe endemic to Africa during the Pliocene to Pleistocene periods. It had a range from Malawi to Central Africa Central Africa is a subregion of the African continent comprising various c ...
''


Characteristics

Fully grown giraffes stand tall, with males taller than females. The average weight is for an adult male and for an adult female. Despite its long neck and legs, its body is relatively short. The skin is mostly gray, or tan, and can reach a thickness of . The long tail ends in a long, dark tuft of hair and is used as a defense against insects. The
coat A coat typically is an outer garment for the upper body as worn by either gender for warmth or fashion. Coats typically have long sleeves and are open down the front and closing by means of buttons, zippers, hook-and-loop fasteners, toggles, a ...
has dark blotches or patches, which can be orange,
chestnut The chestnuts are the deciduous trees and shrubs in the genus ''Castanea'', in the beech family Fagaceae. They are native to temperate regions of the Northern Hemisphere. The name also refers to the edible nuts they produce. The unrelat ...
, brown, or nearly black, surrounded by light hair, usually white or cream coloured. Male giraffes become darker as they grow old. The coat pattern has been claimed to serve as camouflage in the light and shade patterns of savannah woodlands. When standing among trees and bushes, they are hard to see at even a few metres distance. However, adult giraffes move about to gain the best view of an approaching predator, relying on their size and ability to defend themselves rather than on camouflage, which may be more important for calves. Each giraffe has a unique coat pattern. Calves inherit some coat pattern traits from their mothers, and variation in some spot traits is correlated with calf survival. The skin under the blotches may regulate the animal's body temperature, being sites for complex blood vessel systems and large sweat glands. The fur may give the animal chemical defense, as its parasite repellents give it a characteristic scent. At least 11 main aromatic chemicals are in the fur, although indole and 3-methylindole are responsible for most of the smell. Because males have a stronger odour than females, it may also have a sexual function.


Head

Both sexes have prominent horn-like structures called ossicones, which can reach . They are formed from ossified
cartilage Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck an ...
, covered in skin and fused to the skull at the parietal bones. Being vascularised, the ossicones may have a role in thermoregulation, and are used in combat between males. Appearance is a reliable guide to the sex or age of a giraffe: the ossicones of females and young are thin and display tufts of hair on top, whereas those of adult males tend to be bald and knobbed on top. A lump, which is more prominent in males, emerges in the middle of the skull. Males develop calcium deposits that form bumps on their skulls as they age. Multiple sinuses lighten a giraffe's skull. However, as males age, their skulls become heavier and more club-like, helping them become more dominant in combat. The occipital condyles at the bottom of the skull allow the animal to tip its head over 90 degrees and grab food on the branches directly above them with the tongue. With eyes located on the sides of the head, the giraffe has a broad visual field from its great height. Compared to other ungulates, giraffe vision is more
binocular Binocular may refer to: Science and technology * Binocular vision, seeing with two eyes * Binoculars, a telescopic tool * Binocular microscope, binocular viewing of objects through a single objective lens Other uses * Binocular (horse), a thoroug ...
and the eyes are larger with a greater retinal surface area. Giraffes may see in colour and their senses of hearing and
smell Smell may refer to; * Odor, airborne molecules perceived as a scent or aroma * Sense of smell, the scent also known scientifically as olfaction * "Smells" (''Bottom''), an episode of ''Bottom'' * The Smell, a music venue in Los Angeles, Californ ...
are sharp. The ears are movable and the nostrils are slit-shaped, possibly to withstand blowing sand. The giraffe's tongue is about long. It is black, perhaps to protect against sunburn, and can grasp foliage and delicately pick off leaves. The upper lip is flexible and hairy to protect against sharp prickles. The upper jaw has a hard palate instead of front teeth. The molars and
premolar The premolars, also called premolar teeth, or bicuspids, are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant in the permanent set of teeth, making eight premolars total in the mouth ...
s are wide with low crowns on the surface.


Neck

The giraffe has an extremely elongated neck, which can be up to in length. Along the neck is a mane made of short, erect hairs. The neck typically rests at an angle of 50–60 degrees, though juveniles are closer to 70 degrees. The long neck results from a disproportionate lengthening of the
cervical vertebrae In tetrapods, cervical vertebrae (singular: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In ...
, not from the addition of more vertebrae. Each cervical vertebra is over long. They comprise 52–54 per cent of the length of the giraffe's vertebral column, compared with the 27–33 percent typical of similar large ungulates, including the giraffe's closest living relative, the okapi. This elongation largely takes place after birth, perhaps because giraffe mothers would have a difficult time giving birth to young with the same neck proportions as adults. The giraffe's head and neck are held up by large muscles and a nuchal ligament, which are anchored by long thoracic vertebrae spines, giving them a hump. The giraffe's neck vertebrae have
ball and socket joint The ball-and-socket joint (or spheroid joint) is a type of synovial joint in which the ball-shaped surface of one rounded bone fits into the cup-like depression of another bone. The distal bone is capable of motion around an indefinite number o ...
s. The point of articulation between the cervical and thoracic vertebrae of giraffes is shifted to lie between the first and second thoracic vertebrae (T1 and T2), unlike most other ruminants where the articulation is between the seventh cervical vertebra (C7) and T1. This allows C7 to contribute directly to increased neck length and has given rise to the suggestion that T1 is actually C8, and that giraffes have added an extra cervical vertebra. However, this proposition is not generally accepted, as T1 has other morphological features, such as an articulating
rib In vertebrate anatomy, ribs ( la, costae) are the long curved bones which form the rib cage, part of the axial skeleton. In most tetrapods, ribs surround the chest, enabling the lungs to expand and thus facilitate breathing by expanding the ches ...
, deemed diagnostic of thoracic vertebrae, and because exceptions to the mammalian limit of seven cervical vertebrae are generally characterised by increased neurological anomalies and maladies. There are several hypotheses regarding the evolutionary origin and maintenance of elongation in giraffe necks. Charles Darwin originally suggested the "competing browsers hypothesis", which has been challenged only recently. It suggests that competitive pressure from smaller browsers, like kudu,
steenbok The steenbok (''Raphicerus campestris'') is a common small antelope of southern and eastern Africa. It is sometimes known as the steinbuck or steinbok. Description Steenbok resemble small oribi, standing 45–60 cm (16"–24") at the ...
and
impala The impala or rooibok (''Aepyceros melampus'') is a medium-sized antelope found in eastern and southern Africa. The only extant member of the genus '' Aepyceros'' and tribe Aepycerotini, it was first described to European audiences by Germa ...
, encouraged the elongation of the neck, as it enabled giraffes to reach food that competitors could not. This advantage is real, as giraffes can and do feed up to high, while even quite large competitors, such as kudu, can feed up to only about high. There is also research suggesting that browsing competition is intense at lower levels, and giraffes feed more efficiently (gaining more leaf biomass with each mouthful) high in the canopy. However, scientists disagree about just how much time giraffes spend feeding at levels beyond the reach of other browsers, and a 2010 study found that adult giraffes with longer necks actually suffered higher mortality rates under drought conditions than their shorter-necked counterparts. This study suggests that maintaining a longer neck requires more nutrients, which puts longer-necked giraffes at risk during a food shortage. Another theory, the sexual selection hypothesis, proposes the long necks evolved as a secondary sexual characteristic, giving males an advantage in "necking" contests (see below) to establish dominance and obtain access to sexually receptive females. In support of this theory, necks are longer and heavier for males than females of the same age, and males do not employ other forms of combat. However, one objection is it fails to explain why female giraffes also have long necks. It has also been proposed that the neck serves to give the animal greater vigilance.


Legs, locomotion and posture

A giraffe's front and back legs are about the same length. The radius and ulna of the front legs are articulated by the carpus, which, while structurally equivalent to the human wrist, functions as a knee. It appears that a suspensory ligament allows the lanky legs to support the animal's great weight. The hooves of large male giraffes reach in diameter. The fetlock of the leg is low to the ground, allowing the hoof to better support the animal's weight. Giraffes lack dewclaws and interdigital glands. While the pelvis is relatively short, the
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has stretched out crests. A giraffe has only two
gait Gait is the pattern of movement of the limbs of animals, including humans, during locomotion over a solid substrate. Most animals use a variety of gaits, selecting gait based on speed, terrain, the need to maneuver, and energetic efficiency. Di ...
s: walking and galloping. Walking is done by moving the legs on one side of the body, then doing the same on the other side. When galloping, the hind legs move around the front legs before the latter move forward, and the tail will curl up. The movements of the head and neck provide balance and control momentum while galloping. The giraffe can reach a sprint speed of up to , and can sustain for several kilometres. Giraffes would probably not be competent swimmers as their long legs would be highly cumbersome in the water, although they might be able to float. When swimming, the thorax would be weighed down by the front legs, making it difficult for the animal to move its neck and legs in harmony or keep its head above the water's surface. A giraffe rests by lying with its body on top of its folded legs. To lie down, the animal kneels on its front legs and then lowers the rest of its body. To get back up, it first gets on its front knees and positions its backside on top of its hindlegs. It then pulls up the backside upwards and the front legs stand straight up again. At each stage, the animal swings its head for balance. If the giraffe wants to reach down to drink, it either spreads its front legs or bends its knees. Studies in captivity found the giraffe sleeps intermittently around 4.6 hours per day, mostly at night. It usually sleeps lying down; however, standing sleeps have been recorded, particularly in older individuals. Intermittent short "deep sleep" phases while lying are characterised by the giraffe bending its neck backwards and resting its head on the hip or thigh, a position believed to indicate paradoxical sleep.


Internal systems

In mammals, the left recurrent laryngeal nerve is longer than the right; in the giraffe, it is over longer. These nerves are longer in the giraffe than in any other living animal; the left nerve is over long. Each nerve cell in this path begins in the
brainstem The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is cont ...
and passes down the neck along the vagus nerve, then branches off into the recurrent laryngeal nerve which passes back up the neck to the larynx. Thus, these nerve cells have a length of nearly in the largest giraffes. Despite its long neck and large skull, the brain of the giraffe is typical for an ungulate. Evaporative heat loss in the nasal passages keep the giraffe's brain cool. The shape of the skeleton gives the giraffe a small lung volume relative to its mass. Its long neck gives it a large amount of dead space, in spite of its narrow windpipe. The giraffe also has a high tidal volume so the balance of dead space and tidal volume is much the same as other mammals. The animal can still provide enough oxygen for its tissues, and it can increase its respiratory rate and oxygen diffusion when running. The circulatory system of the giraffe has several adaptations for its great height. Its and heart must generate approximately double the blood pressure required for a human to maintain blood flow to the brain. As such, the wall of the heart can be as thick as . Giraffes have relatively high heart rates for their size, at 150 beats per minute. When the animal lowers its head, the blood rushes down fairly unopposed and a rete mirabile in the upper neck, with its large cross-sectional area, prevents excess blood flow to the brain. When it raises again, the blood vessels constrict and push blood into the brain so the animal does not faint. The jugular veins contain several (most commonly seven) valves to prevent blood flowing back into the head from the inferior vena cava and right atrium while the head is lowered. Conversely, the blood vessels in the lower legs are under great pressure because of the weight of fluid pressing down on them. To solve this problem, the skin of the lower legs is thick and tight, preventing too much blood from pouring into them. Giraffes have oesophageal muscles that are strong enough to allow regurgitation of food from the stomach up the neck and into the mouth for rumination. They have four chambered stomachs, which are adapted to their specialized diet. The intestines of an adult giraffe measure more than in length and have a relatively small ratio of small to large intestine. The giraffe has a small, compact liver. Fetuses may be a small gallbladder that vanishes before birth.


Behaviour and ecology


Habitat and feeding

Giraffes usually inhabit savannahs and open woodlands. They prefer by areas dominated by
Acacieae The Mimosoideae are a traditional subfamily of trees, herbs, lianas, and shrubs in the pea family (Fabaceae) that mostly grow in tropical and subtropical climates. They are typically characterized by having radially symmetric flowers, with petals ...
, '' Commiphora'', '' Combretum'' and '' Terminalia'' tree over '' Brachystegia'' which are more densely spaced. The Angolan giraffe can be found in desert environments. Giraffes browse on the twigs of trees, preferring those of the subfamily Acacieae and the genera ''Commiphora'' and ''Terminalia'', which are important sources of calcium and protein to sustain the giraffe's growth rate. They also feed on shrubs, grass and fruit. A giraffe eats around of plant matter daily. When stressed, giraffes may chew on large branches, stripping them of bark. Giraffes are also recorded to chew old bones. During the wet season, food is abundant and giraffes are more spread out, while during the dry season, they gather around the remaining evergreen trees and bushes. Mothers tend to feed in open areas, presumably to make it easier to detect predators, although this may reduce their feeding efficiency. As a ruminant, the giraffe first chews its food, then swallows it for processing and then visibly passes the half-digested cud up the neck and back into the mouth to chew again. The giraffe requires less food than many other herbivores because the foliage it eats has more concentrated nutrients and it has a more efficient digestive system. The animal's faeces come in the form of small pellets. When it has access to water, a giraffe will go no more than three days without drinking. Giraffes have a great effect on the trees that they feed on, delaying the growth of young trees for some years and giving "waistlines" to too tall trees. Feeding is at its highest during the first and last hours of daytime. Between these hours, giraffes mostly stand and ruminate. Rumination is the dominant activity during the night, when it is mostly done lying down.


Social life

Giraffes are usually found in groups that vary in size and composition according to ecological, anthropogenic, temporal, and social factors. Traditionally, the composition of these groups had been described as open and ever-changing. For research purposes, a "group" has been defined as "a collection of individuals that are less than a kilometre apart and moving in the same general direction". More recent studies have found that giraffes have long lasting social groups or cliques based on kinship, sex or other factors, and these groups regularly associate with other groups in larger communities or sub-communities within a fission–fusion society. Proximity to humans can disrupt social arrangements. Masai giraffes in Tanzania sort themselves into different subpopulations of 60–90 adult females with overlapping ranges, each of which differ in reproductive rates and calf mortality. Natal dispersal is male biased, and can include spatial and/or social dispersal. Adult female subpopulations are connected by males into supercommunities of around 300 animals. The number of giraffes in a group can range from one up to 66 individuals. Giraffe groups tend to be sex-segregated although mixed-sex groups made of adult females and young males also occur. Female groups may be
matrilineally Matrilineality is the tracing of kinship through the female line. It may also correlate with a social system in which each person is identified with their matriline – their mother's lineage – and which can involve the inheritance ...
related. Generally females are more selective than males in who they associate with regarding individuals of the same sex. Particularly stable giraffe groups are those made of mothers and their young, which can last weeks or months. Young males also form groups and will engage in playfights. However, as they get older, males become more solitary but may also associate in pairs or with female groups. Giraffes are not
territorial A territory is an area of land, sea, or space, particularly belonging or connected to a country, person, or animal. In international politics, a territory is usually either the total area from which a state may extract power resources or an ...
, but they have home ranges that vary according to rainfall and proximity to human settlements. Male giraffes occasionally roam far from areas that they normally frequent. Early biologists suggested giraffes were mute and unable to create enough air flow to vibrate their vocal folds. To the contrary; they have been recorded to communicate using snorts, sneezes, coughs, snores, hisses, bursts, moans, grunts, growls and flute-like sounds. During courtship, males emit loud coughs. Females call their young by bellowing. Calves will emit bleats, mooing and mewing sounds. Snorting and hissing is associated with vigilance. During nighttime, giraffes appear to hum to each other above the infrasound range. The purpose is unclear. Dominant males display to other males with an erect posture; holding the chin and head up while walking stiffly and displaying their side. The less dominant show submissiveness by dropping the head and ears, lowering the chin and fleeing.


Reproduction and parental care

Reproduction in giraffes is broadly polygamous: a few older males mate with the fertile females. Females can reproduce throughout the year and experience oestrus cycling approximately every 15 days. Female giraffes in oestrous are dispersed over space and time, so reproductive adult males adopt a strategy of roaming among female groups to seek mating opportunities, with periodic hormone-induced rutting behaviour approximately every two weeks. Males prefer young adult females over juveniles and older adults. Male giraffes assess female fertility by tasting the female's urine to detect oestrus, in a multi-step process known as the flehmen response. Once an oestrous female is detected, the male will attempt to court her. When courting, dominant males will keep subordinate ones at bay. A courting male may lick a female's tail, lay his head and neck on her body or nudge her with his ossicones. During copulation, the male stands on his hind legs with his head held up and his front legs resting on the female's sides. Giraffe
gestation Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregna ...
lasts 400–460 days, after which a single calf is normally born, although twins occur on rare occasions. The mother gives birth standing up. The calf emerges head and front legs first, having broken through the fetal membranes, and falls to the ground, severing the umbilical cord. A newborn giraffe is tall. Within a few hours of birth, the calf can run around and is almost indistinguishable from a one-week-old. However, for the first one to three weeks, it spends most of its time hiding, its coat pattern providing camouflage. The ossicones, which have lain flat in the womb, raise up in a few days. Mothers with calves will gather in nursery herds, moving or browsing together. Mothers in such a group may sometimes leave their calves with one female while they forage and drink elsewhere. This is known as a " calving pool". Calves are at risk of predation, and a mother giraffe will stand over them and kick at an approaching predator. Females watching calving pools will only alert their own young if they detect a disturbance, although the others will take notice and follow. Calves first ruminate at four to six months and stop nursing at six to eight months. Young may not reach independence until they are 14 months old. Females become sexually mature when they are four years old, while males become mature at four or five years.
Spermatogenesis Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testis. This process starts with the mitotic division of the stem cells located close to the basement membrane of the tubule ...
in male giraffes begins at three to four years of age. Males must wait until they are at least seven years old to gain the opportunity to mate.


Necking

Male giraffes use their necks as weapons in combat, a behaviour known as "necking". Necking is used to establish dominance and males that win necking bouts have greater reproductive success. This behaviour occurs at low or high intensity. In low-intensity necking, the combatants rub and lean on each other. The male that can keep itself more upright wins the bout. In high-intensity necking, the combatants will spread their front legs and swing their necks at each other, attempting to land blows with their ossicones. The contestants will try to dodge each other's blows and then prepare to counter. The power of a blow depends on the weight of the skull and the arc of the swing. A necking duel can last more than half an hour, depending on how well matched the combatants are. Although most fights do not lead to serious injury, there have been records of broken jaws, broken necks, and even deaths. After a duel, it is common for two male giraffes to caress and court each other. Such interactions between males have been found to be more frequent than heterosexual coupling. In one study, up to 94 percent of observed mounting incidents took place between males. The proportion of same-sex activities varied from 30 to 75 percent. Only one percent of same-sex mounting incidents occurred between females.


Mortality and health

Giraffes have high adult survival probability, and an unusually long lifespan compared to other ruminants, up to 38 years. Because of their size, eyesight and powerful kicks, adult giraffes are usually not subject to predation, although
lion The lion (''Panthera leo'') is a large Felidae, cat of the genus ''Panthera'' native to Africa and India. It has a muscular, broad-chested body; short, rounded head; round ears; and a hairy tuft at the end of its tail. It is sexually dimorphi ...
s may regularly prey on individuals up to . Giraffes are the most common food source for the big cats in
Kruger National Park Kruger National Park is a South African National Park and one of the largest game reserves in Africa. It covers an area of in the provinces of Limpopo and Mpumalanga in northeastern South Africa, and extends from north to south and from ea ...
, comprising nearly a third of the meat consumed, although only a small portion of the giraffes were probably killed by predators, as a majority of the consumed giraffes appeared to be scavenged. Adult female survival is significantly correlated with the number of social associations. Calves are much more vulnerable than adults and are also preyed on by leopards, cheetahs, Nile crocodiles,
spotted hyena The spotted hyena (''Crocuta crocuta''), also known as the laughing hyena, is a hyena species, currently classed as the sole extant member of the genus ''Crocuta'', native to sub-Saharan Africa. It is listed as being of least concern by the IUC ...
s and wild dogs. A quarter to a half of giraffe calves reach adulthood. Calf survival varies according to the season of birth, with calves born during the dry season having higher survival rates. The local, seasonal presence of large herds of migratory wildebeests and zebras reduces predation pressure on giraffe calves and increases their survival probability. In turn, it has been suggested that other ungulates may benefit from associating with giraffes, as their height allows them to spot predators from further away. Zebras were found to access predation risk by watching giraffes and spend less time looking around when giraffes are present. Some parasites feed on giraffes. They are often hosts for ticks, especially in the area around the genitals, which have thinner skin than other areas. Tick species that commonly feed on giraffes are those of genera '' Hyalomma'', '' Amblyomma'' and '' Rhipicephalus''. Giraffes may rely on red-billed and yellow-billed oxpeckers to clean them of ticks and alert them to danger. Giraffes host numerous species of internal parasites and are susceptible to various diseases. They were victims of the (now eradicated) viral illness rinderpest. Giraffes can also suffer from a skin disorder, which comes in the form of wrinkles, lesions or raw fissures. As much as 79% of giraffes have symptoms of the disease in Ruaha National Park, but it did not cause mortality in
Tarangire The Tarangire River is a perennial river located in central Manyara Region in the eastern branch of the East African Rift Valley, within northern Tanzania. Course The headwaters of the Tarangire River are in the highlands and escarpments of Baba ...
and is less prevalent in areas with fertile soils.


Relationship with humans


Cultural significance

With its lanky build and spotted coat, the giraffe has been a source of fascination throughout human history, and its image is widespread in culture. It has represented flexibility, far-sightedness, femininity, fragility, passivity, grace, beauty and the continent of Africa itself. Giraffes were depicted in art throughout the African continent, including that of the Kiffians,
Egyptians Egyptians ( arz, المَصرِيُون, translit=al-Maṣriyyūn, ; arz, المَصرِيِين, translit=al-Maṣriyyīn, ; cop, ⲣⲉⲙⲛ̀ⲭⲏⲙⲓ, remenkhēmi) are an ethnic group native to the Nile, Nile Valley in Egypt. Egyptian ...
, and
Kushites The Kingdom of Kush (; Egyptian: 𓎡𓄿𓈙𓈉 ''kꜣš'', Assyrian: ''Kûsi'', in LXX grc, Κυς and Κυσι ; cop, ''Ecōš''; he, כּוּשׁ ''Kūš'') was an ancient kingdom in Nubia, centered along the Nile Valley in what i ...
. The Kiffians were responsible for a life-size rock engraving of two giraffes, dated 8,000 years ago, that has been called the "world's largest rock art petroglyph". How the giraffe got its height has been the subject of various African folktales. The
Tugen people The Tugen are a sub tribe of the Kalenjin people alongside the Nandi, Kipsigis, Keiyo, Pokot, Marakwet, Sabaot, Ogiek, Lembus and Sengwer sub-tribes. They occupy Baringo County and some parts of Nakuru County and Elgeyo Marakwet County in the ...
of modern Kenya used the giraffe to depict their god Mda. The Egyptians gave the giraffe its own hieroglyph; 'sr' in Old Egyptian and 'mmy' in later periods. Giraffes have a presence in modern Western culture. Salvador Dalí depicted them with burning manes in some of his surrealist paintings. Dali considered the giraffe to be a masculine symbol, and a flaming giraffe was meant to be a "masculine cosmic apocalyptic monster". Several children's books feature the giraffe, including David A. Ufer's ''The Giraffe Who Was Afraid of Heights'',
Giles Andreae Giles Andreae (born 16 March 1966) is a British writer and illustrator. He is the creator of the stickman poet Purple Ronnie, the humorous artist / philosopher Edward Monkton, and the author of Giraffes Can't Dance, along with many other books fo ...
's ''Giraffes Can't Dance'' and
Roald Dahl Roald Dahl (13 September 1916 – 23 November 1990) was a British novelist, short-story writer, poet, screenwriter, and wartime fighter ace of Norwegian descent. His books have sold more than 250 million copies worldwide. Dahl has be ...
's '' The Giraffe and the Pelly and Me''. Giraffes have appeared in animated films, as minor characters in Disney's '' The Lion King'' and '' Dumbo'', and in more prominent roles in '' The Wild'' and the '' Madagascar'' films. Sophie the Giraffe has been a popular teether since 1961. Another famous fictional giraffe is the Toys "R" Us mascot
Geoffrey the Giraffe Geoffrey, Geoffroy, Geoff, etc., may refer to: People * Geoffrey (name), including a list of people with the name * Geoffroy (surname), including a list of people with the name * Geoffrey of Monmouth (c. 1095–c. 1155), clergyman and one of the ...
. The giraffe has also been used for some scientific experiments and discoveries. Scientists have used the properties of giraffe skin as a model for
astronaut An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a human spaceflight program to serve as a commander or crew member aboard a spacecraft. Although generally r ...
and
fighter pilot A fighter pilot is a military aviator trained to engage in air-to-air combat, air-to-ground combat and sometimes electronic warfare while in the cockpit of a fighter aircraft. Fighter pilots undergo specialized training in aerial warfare and ...
suits because the people in these professions are in danger of passing out if blood rushes to their legs. Computer scientists have modeled the coat patterns of several subspecies using reaction–diffusion mechanisms. The
constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the e ...
of
Camelopardalis Camelopardalis is a large but faint constellation of the northern sky representing a giraffe. The constellation was introduced in 1612 or 1613 by Petrus Plancius. Some older astronomy books give Camelopardalus or Camelopardus as alternative for ...
, introduced in the seventeenth century, depicts a giraffe. The Tswana people of Botswana traditionally see the constellation Crux as two giraffes— Acrux and Mimosa forming a male, and Gacrux and Delta Crucis forming the female.


Captivity

The Egyptians were among the earliest people to keep giraffes in captivity shipped them around the Mediterranean. The giraffe was among the many animals collected and displayed by the Romans. The first one in Rome was brought in by
Julius Caesar Gaius Julius Caesar (; ; 12 July 100 BC – 15 March 44 BC), was a Roman general and statesman. A member of the First Triumvirate, Caesar led the Roman armies in the Gallic Wars before defeating his political rival Pompey in a civil war, and ...
in 46 BC. With the fall of the Western Roman Empire, the housing of giraffes in Europe declined. During the Middle Ages, giraffes were known to Europeans through contact with the Arabs, who revered the giraffe for its peculiar appearance. Individual captive giraffes were given celebrity status throughout history. In 1414, a giraffe from Malindi was taken to China by explorer Zheng He and placed in a Ming dynasty zoo. The animal was a source of fascination for the Chinese people, who associated it with the mythical Qilin. The Medici giraffe was a giraffe presented to Lorenzo de' Medici in 1486. It caused a great stir on its arrival in Florence. Zarafa, another famous giraffe, was brought from Egypt to Paris in the early 19th century as a gift for Charles X of France. A sensation, the giraffe was the subject of numerous memorabilia or "giraffanalia". Giraffes have become popular attractions in modern zoos, though keeping them healthy is difficult as they require vast areas and need to eat large amounts of browse. Captive giraffes in North America and Europe appear to have a higher mortality rate than in the wild; the most common causes being poor husbandry, nutrition and management. Giraffes in zoos display stereotypical behaviours, particularly the licking of inanimate objects and pacing. Zookeepers may offer various activities to stimulate giraffes, including training them to take food from visitors.
Stable A stable is a building in which livestock, especially horses, are kept. It most commonly means a building that is divided into separate stalls for individual animals and livestock. There are many different types of stables in use today; the ...
s for giraffes are built particularly high to accommodate their height.


Exploitation

Giraffes were probably common targets for hunters throughout Africa. Different parts of their bodies were used for different purposes. Their meat was used for food. The tail hairs served as flyswatters, bracelets, necklaces, and threads. Shields, sandals, and drums were made using the skin, and the strings of musical instruments were from the tendons. In
Buganda Buganda is a Bantu peoples, Bantu kingdom within Uganda. The kingdom of the Baganda, Baganda people, Buganda is the largest of the traditional kingdoms in present-day East Africa, consisting of Buganda's Districts of Uganda, Central Region, inclu ...
, the smoke of burning giraffe skin was traditionally used to treat nose bleeds. The Humr people of Kordofan consume the drink Umm Nyolokh, which is prepared from the liver and
bone marrow Bone marrow is a semi-solid tissue found within the spongy (also known as cancellous) portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production (or haematopoiesis). It is composed of hematopoietic ce ...
of giraffes. Richard Rudgley hypothesised that Umm Nyolokh might contain
DMT ''N'',''N''-Dimethyltryptamine (DMT or ''N'',''N''-DMT, SPL026) is a substituted tryptamine that occurs in many plants and animals, including human beings, and which is both a derivative and a structural analog of tryptamine. It is used as a ...
. The drink is said to cause hallucinations of giraffes, believed to be the giraffes' ghosts, by the Humr.


Conservation status

In 2016, giraffes were assessed as
Vulnerable Vulnerable may refer to: General * Vulnerability * Vulnerability (computing) * Vulnerable adult * Vulnerable species Music Albums * ''Vulnerable'' (Marvin Gaye album), 1997 * ''Vulnerable'' (Tricky album), 2003 * ''Vulnerable'' (The Used album) ...
from a conservation perspective by the IUCN. In 1985, it was estimated there were 155,000 giraffes in the wild. This declined to over 140,000 in 1999. Estimates as of 2016 indicate there are approximately 97,500 members of ''Giraffa'' in the wild. The Masai and reticulated subspecies are endangered, and the Rothschild subspecies is near threatened. The Nubian subspecies is critically endangered. The primary causes for giraffe population declines are habitat loss and direct killing for
bushmeat Bushmeat is meat from wildlife species that are hunted for human consumption, most often referring to the meat of game in Africa. Bushmeat represents a primary source of animal protein and a cash-earning commodity for inhabitants of humid tropi ...
markets. Giraffes have been extirpated from much of their historic range, including
Eritrea Eritrea ( ; ti, ኤርትራ, Ertra, ; ar, إرتريا, ʾIritriyā), officially the State of Eritrea, is a country in the Horn of Africa region of Eastern Africa, with its capital and largest city at Asmara. It is bordered by Ethiopia ...
,
Guinea Guinea ( ),, fuf, 𞤘𞤭𞤲𞤫, italic=no, Gine, wo, Gine, nqo, ߖߌ߬ߣߍ߫, bm, Gine officially the Republic of Guinea (french: République de Guinée), is a coastal country in West Africa. It borders the Atlantic Ocean to the we ...
,
Mauritania Mauritania (; ar, موريتانيا, ', french: Mauritanie; Berber: ''Agawej'' or ''Cengit''; Pulaar: ''Moritani''; Wolof: ''Gànnaar''; Soninke:), officially the Islamic Republic of Mauritania ( ar, الجمهورية الإسلامية ...
and Senegal. They may also have disappeared from Angola, Mali, and Nigeria, but have been introduced to
Rwanda Rwanda (; rw, u Rwanda ), officially the Republic of Rwanda, is a landlocked country in the Great Rift Valley of Central Africa, where the African Great Lakes region and Southeast Africa converge. Located a few degrees south of the Equator ...
and
Eswatini Eswatini ( ; ss, eSwatini ), officially the Kingdom of Eswatini and formerly named Swaziland ( ; officially renamed in 2018), is a landlocked country in Southern Africa. It is bordered by Mozambique to its northeast and South Africa to its no ...
. , there were more than 1,600 in captivity at Species360-registered zoos. Habitat destruction has hurt the giraffe. In the
Sahel The Sahel (; ar, ساحل ' , "coast, shore") is a region in North Africa. It is defined as the ecoclimatic and biogeographic realm of transition between the Sahara to the north and the Sudanian savanna to the south. Having a hot semi-arid c ...
, the need for firewood and grazing room for livestock has led to deforestation. Normally, giraffes can coexist with livestock, since they avoid direct competition by feeding above them. In 2017, severe droughts in northern Kenya led to increased tensions over land and the killing of wildlife by herders, with giraffe populations being particularly hit. Protected areas like national parks provide important habitat and anti-poaching protection to giraffe populations. Community-based conservation efforts outside national parks are also effective at protecting giraffes and their habitats. Private game reserves have contributed to the preservation of giraffe populations in eastern and southern Africa. The giraffe is a protected species in most of its range. It is the national animal of Tanzania, and is protected by law, and unauthorised killing can result in imprisonment. The UN backed Convention of Migratory Species selected giraffes for protection in 2017. In 2019, giraffes were listed under Appendix II of the Convention on International Trade in Endangered Species ( CITES), which means international trade including in parts/derivatives is regulated. Translocations are sometimes used to augment or re-establish diminished or extirpated populations, but these activities are risky and difficult to undertake using the best practices of extensive pre- and post-translocation studies and ensuring a viable founding population. Aerial survey is the most common method of monitoring giraffe population trends in the vast roadless tracts of African landscapes, but aerial methods are known to undercount giraffes. Ground-based survey methods are more accurate and can be used in conjunction with aerial surveys to make accurate estimates of population sizes and trends.


See also

* Fauna of Africa * Giraffe Centre *
Giraffe Manor Giraffe Manor is a small hotel in the Lang'ata suburb of Nairobi, Kenya which, together with its associated Giraffe Centre, serves as a home to a number of endangered Rothschild's giraffes, and operates a breeding programme to reintroduce breedi ...
- hotel in Nairobi with giraffes


References


External links


Giraffe Conservation Foundation
{{Authority control Articles containing video clips Fauna of Sub-Saharan Africa Herbivorous mammals Mammal genera Mammals of Africa National symbols of Tanzania Vulnerable animals Vulnerable biota of Africa